1. Field of the Invention
The present invention relates to an apparatus for recording and playing back of two digital video signals having different amounts of data in each frame.
2. Description of the Prior Art
As high definition video signals (referred to as HD signals hereinafter) are now proved advantageous, the development of HDVCRs for recording HD signals have been accelerated. Such HDVCRs are however designed for analog recording and the form of record on a tape medium is different between the HD signals and the existing standard video signals (referred to as SD signals hereinafter). Hence, there is no way to process both the HD and SD signals with the same circuit. Conventional VCRs for digital recording (referred to as DVCRs) are substantially prepared for broadcast service with either HD and SD signals. Also, each DVCR is separately designed for processing HD or SD signals thus having no compatibility. Although such professional-use DVCRs allow only one type of signal, HD or SD signals, to be recorded and played back, they are used for broadcast service and will be accepted in spite of their inability for processing both the HD and SD signals with the same circuitry.
However, home-use DVCRs which will before long be introduced in the market never appreciate the foregoing drawback that each type signal is processed by its specific DVCR. In particular, the drawback will be emphasized in the respects of overall cost, installation space, and operational difficulty. As understood, none of the conventional DVCRs failing to have a compatible arrangement for the recording of both HD and SD signals is eligible for use as a home-use DVCR. Also, such inability of-a conventional DVCR leads to discourage improvements in its performance. If each HD signal carries data as much as 4 times the data of an SD signal, one DVCR which can process HD signals for recording (referred to as an HDDVCR) will be capable of processing 4 times the data that can be processed by a typical SD signal DVCR (referred to as an SDDVCR). Unfortunately, the conventional HDDVCR has no capability for processing SD signals and cannot appropriate its bulk signal processing ability to the recording of more SD signals. In other words, the conventional HDDVCR fails to improve its operational capability.